Artificial hand



T. OPUSZENSKI ARTIFICIAL HAND Feb. 23, 1954 Filed Ju1y'24, 1951 7 Sheets-Sheet l INVENTOR THEODORE OPUSZENSKI BY 49 ATTO EY Feb. 23, 1954 T. OPUSZENSKI 2,659,727

ARTIFICIAL HAND Filed July 24, 1951 7 Sheets-Sheet 2 FIG. 2

INVENTOR THEODORE OPUSZENSKI 'r. OPUSZENSKI ARTIFICIAL HAND Feb. 23, 1954 7 Sheets-Sheet I5 Filed July 24, 1951 \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\vw$vv 1 4//// gfl INVENTOR THEODORE OPUSZENSKI 49 I ATTORN Feb, 23, 1954 'r. OPUSZENSKI 2,669,727

ARTIFICIAL HAND Filed July 24, 1951 7 Sheets-Sheet 4 INVENTOR THEODORE O USZENSKI ATTORN Feb. 23, 1954 T. OPUSZENSKI 2,669,727

ARTIFICIAL HAND Filed July 24, 1951 7 Sheets-Sheet 6 THEODORE OPUSZENSKI Feb. 23, 1954 T. OPUSZENSKI 2,669,

ARTIFICIAL HAND 7 Sheets-Sheet '7 7 Filed July 24, 1951 FIG. l6 l ,lss'

INVENTOR I THEODORE OPUSZENSKI Patented Feb. 23, 1954 UNITED STATES ATENT OFFICE ARTIFICIAL HAND Theodore Opuszenski, Stamford, Conn.

Application July 24, I951, Serial No. 238,336

This invention concerns a new type artificial hand which is muscle actuated and controlled and which so simulates the mechanical movements of the human hand that its user is able to accomplish many of the same actions with his artificial hand that he could accomplish with a real hand and in substantially the same manner in which such movement would be made.

'It is a primary object of my invention to provide an artificial hand which may be made to look like a real human hand and, at the same time, which is useful to accomplish many everyday tasks. Prior art artificial hands are, for the most part, either ornamental or useful, but not both ornamental and useful. Even the more recently developed hands which are claimed to be both useful and natural in apearance are limited in their usefulness, and look natural only to the casual observer when the hand is at rest. By way of contrast, my novel hand appears natural while in motion as well as while at rest. For example, my hand has three-segment digits which bend in a natural way at three joints. Likewise, the manner of bending my artificial thumb, which swings through a large are about a near-hand knuckle at a large angle with the near-hand finger knuckles, amounts to a particularly significant advance. This large arc swing of the thumb together with correct finger movement permits my hand to grasp larger objects than has been heretofore possible with artificial hands. Likewise, the thumb and forefinger or middle finger of my hand are actually oposed so that objects may be grasped firmly therebetween.

It is also an object of my invention to cause actuation of my artificial hand in a natural way. Rather than using a natural muscle connection requiring surgery, such as a pin piercing a forearm muscle, and rather than using a relatively easily operated means relying upon unnatural movement of some sort for actuation of the hand, my invention employs a simple switch which may be closed by the flexing of those muscles which would normally move the hand. Thus, actuation is accomplished with a minimum of effort in a movement which is undetectable to the most careful observer. This type of actuation also makes it possible to learn to use the artificial hand in a minimum of time because it is possible in many cases to use the same muscle movements in actuating theartificial hand as those used by a person in moving his real hand.

Another object of my invention is to produce an artificial hand which is powerful, yet con- 28 Claims. (Cl. 312.7)

trollable. My power supply includes a fluid pressure storage means which permits the rapid build up of fluid pressure, which. in turn is used to drive the hand movement mechanism. Thus, if the hand is otherwise made strong enough, it is possible to crush a tin can with my artificial hand. By contrast, a release valve is provided which may be used at any time to partially or fully release the pressure so that with practice the wearer should be able to control the pressure of the digits in grasping and thus be able to handle fragile objects without breaking or crushing them.

Still another object of my invention is to produce a rugged artificial hand capable of withstanding a great amount of mechanical battering. The design of my digits makes it possible to use heavy guage materials at almost all points in the fabrication of the digits, and the shapes of the digital members further add to their strength. Likewise, the drive means and the digital coupling, one digit to another and to the power supply, is of rugged construction and quite simple design. In general, the use of fragile components has been avoided in my artificial hand.

Yet another object of my invention is to provide a compact artificial hand. My hand is unusually compact in that all power supply and drive means may be included in the hand itself, below the wrist. Only the socket and support members, the actuating switches, and the energy supply (usually batteries) are outside of the hand. Nevertheless, my artificial hand is not bulky or unnatural in appearance, and no parts of my artificial hand protrude to interfere With its operation in any way.

It is another object of my invention to make my artificial hand light. Lightness is of great importance because a heavy hand, no matter how theoretically useful, cannot be moved about with ease and natural movement. My artificial hand is extremely light. Most of its parts, particularly the parts of the digits and the drive mechanism, can be made of light metals or possibly even of plastics. The natural compactness of my hand makes for lightness, and its simplicity eliminates a great many weight-adding pieces.

Many other advantages of my invention will be evident from the discussion hereafter. For a better understanding of my invention reference is made to the following drawings:

Fig. 1 shows a perspective view of a preferred construction of my artificial hand partially in SGGtiQIl- Fig. 2 illustrates my hand partially in section from above.

Fig. 3 shows an elevational view of one finger from above.

Fig. 4 shows in section a side view of the same finger.

Fig. 5 illustrates, in a sectional view, the movement of the finger of Figs. 3 and 4 and specifically shows the tip segment fully bent.

Fig. 6 illustrates, in a sectional view, the finger of Figs. 3 and'4 in essentially the position that it would occupy in a closed hand.

Fig. 7 shows a simplified finger structure of my invention which illustrates the principle of-operation of my artificial digits.

Fig. 8 shows a cross sectionalview from above of one form of my artificial thumb.

Fig. 9 shows a sectional view of the same thumb taken along line 9-9 of Fig. 8.

Fig. 10 illustrates in a sectional view from above la'imodifid form =omy artificial thumb.

'Fig. 11' shows the Fig; 10: thumb": construction in aside elevational 'view.

i Fig; 12 shows'in partial section the'ldrive 'coupling means used in the preferred form -of my invention to" drive the artificialihand.

: Fig. 13 shows the internali construction-ore preferred "type ofopower unit :in" partial section.

- Fig. 14 shows a sectionfof lthe samg-power'unit takenat right angles to: the section of Fig 13 along line 14-14 of FigL'13.

'Fig. 15 shows in elevation a socket' and support means to be used with my artificial hand ior a lower-arm amputee, said socket andsupport being in the extended arm position.

i Fig. 16 shows in-partial'sectiori-the socket and support of Fig. 15 in the bent-arm position.

Fig; 17 shows in elev'ationthe relatively'rotatable portions of my artificial wrist;

Fig. -'18 showsinpartial-se'ction the switchelement of the actuating circuit formy artificial hand.

Fig. 19 shows schematically a 'circuitwhi'ch may be employed in operating the power-supply for my artificial hand.

Referring to Fig. 1, my novel artificial 'harid mechanism'issriown as a whole, up'to' and inclu'dingthe wrist, butwithout'socket' or'support means. "The relative simplicity andruggdness of this structure'is immediatelyapparent. Its

relative simplicitymakes itpossible to make this handboth lightand compact without sacrificing power. Its lightness is important because it lessens the lcadwhich the amputee wearermu'st lift. Its compactness permits theilight, compact power supply'unit' to'b advantageously located within the hand itselfJThus a complete operational mechanism is included within? the hand below the wristwithout telltale bulkor'weight so that'only the energy source needtbe located out-. side of the hand. Hence, my'handisparticulan ly valuable for .a' wri'stlevel' amputee. However, it is an advantage.ofmy'lhand that 'it maybe adapted for use no matter at what level the amputation occurs.

The structure illustrated in Fig. 1 may be afilxed to-any known type of support or socket. Many methods of attachment of the hand of the present invention will occurto one skilled inithe art. -When the actuati0nmeans. for driving closed and releasing the. artificial hand. is electrically powered, as in the case of the. structure illustrated in Fig. 1, the necessary energy source may consist of batteries which may-becarried in any convenient location on the body o t-lthe .:power or ease of movement. This drawing will be referred to from time to time in the following discussion.

Figs. 3 and a show in detail the preferred construction of artificial fingers for use with my artificialrhand. Although the segment dimensions and the overall size of each finger may differ from one to another in the same hand and from hand to hand, the construction of each of the four fingers is advantageously"mechanically the same. Like the real human finger, but unlike manypriorart artificial digits, these fingers each have three segments which I prefer to term the tip,'midd1e and near-hand segments. Near-hand is used in the sense of being near the palm'of the hand.

The tip segment 23 is mechanically a single piece, but it may have a contacting surfaceZI made of resilient material, such'as rubber, in order to simulate the give found in the touch of realfingers. A pair of tongue flanges 22 and 23 extend from the tip segment-2 0' toward'the'middie segment and form the'means whereby the tip segment is joined to' the respective'members of the middle segment.

' Parallel pins 2 3 amrzs connect flanges 22 and 23 to the forked flangesie and 21 respectively, the prongs of which forked fianges lie'on two sides'of flanges 22 and;23."-'The'forked'fiange 26 is connected to middle segment In'ember2B-whi1e forked flange 2? "terminates middle segment member 29. Flange ZS may'be afiixed to member 28 in any appropriate manner such-as bycollar 36 which'may be welded or otherwisepermanently attached to'member 28. 'Memberslfl-andrfl are coaxial; member fitlbeing tubular; and surrounding member 29. While the members 28 and 29 are independent of one another, in that they are not attached in any way, member -29'fits close within member 26, thereby restricting relative movement between: segment members to that in the direction of their elongation. A radial shoulder 3 l, formed by the reduction of the inner diameter of tubular member 28, opposeswradial shoulder 32, formed by the reductionof the diameter of'member 29. Flanges 33 and 34-; extending toward the near=hand segment,-terminate the near-hand end of the middle segment members 28 and- 29 respectively. Flange-33 may b connected to member 28 by a collar 35. Flange-34 is an extension of the member 29.

The near-hand segment of the finger is composed of member 36 coaxially surroundedby tubular .member 31. These .members correspondlto the middle segment members 29 and -28. -A collar 38, similar to collar 30 usedto. connect flange 26 to .member. 28, may be used toaffix fork-.-like flange 39 .to member. 31. Pin 40 joinsfianges 33 and 39. Forked .flange' than extension otmember 36, .is connected tolfiange 34 by pin 42 which is parallel to pin 48. The near-hand end of tubu-.

lar member 3'! terminates in knuckle-member 43 which may advantageously by a. cylindrical. or tu ular member'through'whichmembei 3'!- passes Many variations are possible in the shape or.

arrangement of the extension members or flanges which make possible the rotatable connection of members in the adjacent segments. For instance, fork and tongue flanges may be interchanged.-

Finger movement is illustrated in Figs. 5 and 6. Finger movement is caused by the application of parallel opposing forces to the near-hand segment members 36 and 3? in the direction of their elongation. These parallel forces usually appear in the form of a force causing the relative withdrawal of member 36 toward the palm of the hand while the other force tends to hold member 3! in place or to cause its relative movement in the direction opposite that of member 36. Because of the rotatable connections at 62 and 25, the withdrawal of member 35 will cause a withdrawal of middle segment member 29 and tend to cause a withdrawal of tip segment 2E3. Tip segment cannot be withdrawn, however, because it is also rigidly, though rotatably, connected by pin 24 to member 28 which in turn is connected by pin 40 to the relatively stationary near-hand segment member 31. Thus, when pin 25 is withdrawn, the opposition to withdrawal presented at pin 24 will produce rotation of tip 28) about pin 24. The change in the position of tip 20 is accommodated by relative rotation between tip member 20 and middle segment member 29.

Rotation of tip segment 28 relative to the middle segment will continue until the relative movement between the middle segment members is stopped. Thus, the amount of bending of the tip segment 20 may be controlled by limiting the amount of relative motion between middle segment members 28 and 29. This relative motion is limited by opposing shoulders 3| and 32 on members 28 and 29 respectively.

When shoulders 35 and 32 abut, no further relative withdrawal of member 29 is possible.

Therefore, the middle segment members 28 and 29 will react as a unit, not unlike the tip segment, to forces tending to produce such a withdrawal movement. Thus, the withdrawal of member 35 will tend to cause withdrawal of the whole middle segment because of connection 42. However, the near-hand member 3! will tend to prevent withdrawal of the middle segment because of connection 40. The opposition to the withdrawal of the middle segment will therefore produce rotation about pin 48. This rotation is accompanied by relative rotation between middle segment member 29 and near-hand segment member 36.

It will be apparent that when rotation of the tip segment 25! relative to the middle segment takes place around pin 24, pin 25 tends also to rotate around pin 24. Likewise, when rotation of the middle segment relative to the near-hand segment takes place around pin 40, pin 52 tends also to rotate around pin 46. In each of these instances complete rotation of one pin around reason than because the pivot which tends to rotate about the other is the one which connects the inner members of the segments. In fact} the confining nature of tubular outer members 28 and 31 would seem to limit inner members 29 1 and 3B, hence the pins affixed to them, to motion I along lines parallel to the direction of elongation.

However, the relative bending between digital segmentsis seldom more than 30. For such small angles, the chord differs very little from its arc of the circle described in bending. The

effect of the arc is minimized by placingthe pins so that the chord of the arc is essentially parallel" to the direction of elongation. Then the important component of motion will always be parallel to the direction of motion with minor components of motion perpendicular to this direction and reversing is direction midway between the unbent and the fully bent portions of the particular joint. As a practical matter, this means that pin 25 is advantageously placed ahead (further from the palm of the hand) of pin 24 in the direction of elongation of the middle segment when the tip segment is unbent. By the same token for ideal positioning, pin 25 should be as far behind pin 2G in the fully bent position as it is ahead in the unbent position. Likewise, pin 42 should be as far ahead of pin 49 in the direction of elongation of the near-hand segment when the middle segment begins to bend relative to the near-hand segment as it is behind pin 40 when the middle segment is fully bent. This joint presents an additional problem, however, as the inner member 2c of the middle segment, including pin 42,

must move in this same direction even before relative bending between the middle and nearv hand segments begins. Thus pin 42 is advantageously placed so that its are around pivot 4!] begins when pivot 42 is as far ahead of pin 40 in the direction of elongation of the near-hand segment as it is behind pin 49 when fully bent. It should also be noted that only small distances are involved between the pins relative to the length of the segments.

Although the perpendicular component of relative motion between inner and outer segment members may be minimized as above described, very close tolerances between the respective members of each segment and between the various pins and the members which they penetrate will prohibit any motion perpendicular to the direction of elongation of these segments. Thus, in my artificial hand locseness or play is intentionally left either in the pin connection or between the members of a segment. If the play is left at the connections, it is advantageously done 7 by aifixing the pin permanently to one member and enlarging the hole through which it passes in-;the other member.

It may also be noted in passing that the ends of flanges are advantageously rounded to insure complete freedom in rotational movement, particularly where the flanges are short and over lap one another for a large part of their length.

Fig. 7 shows the most simplified version of my artificial digit which version demonstrates the basic operation and structure of my artificial digit. While this simple construction or a modification thereof might be employed in lieu of the more complicated structure above described, it lacks the strength and self-protecting qualities of the coaxial construction. Nevertheless, it serves to illustrate the basic simplicity of my artificial finger.

As before mentioned,

like the human fingeiyf ,my artificial finger has three segments. 'The tip segment 20' is advantageously composed of a" single, somewhat.-ielongatedmember,eaThevmid-fdle nsegment and the' near-hand segment: are-- each. composed of the rigid essentially parallel;

elongated -members'-28'- and :29 and I 31"and 33 respectively. Each of the middlefsegmentmem-' bers-285 and 29is-joined' at one-end-to the-tip? segmentby 'pin. means 24 and-.25' permitting rotation? The oppositeend of each middle seg-- mentmember 28" and-281:. is connected-to the corresponding member 31"and 36' in the nearhand segment by pins;4li' and=42' respectively To causeithe fingerof Fig. 7 to bend, the nearhandy-segment:members-JS and .3?- are acted upon by-forces. which tend to withdraw one memher-(36L) relative to :the other and along .a line parallel-to the other. Withdrawalof member 36':will cause member 29'-to be withdrawn also- These opposing forces are able to cause-rotation of I tip 29 about pin connection 24, however, be-' causepinconnection 25'. also permits rotation or bending :of tip 28' relative to the other middle segment-member 29' which must remain essentiallyparallel to member 28';

Tip'segment -2B'- will continue to rotate-about connection 24' as longras connection 25 'iswithdrawneor as-=long as the relative movement between-parallel .members28' and 29' continues.

The-amount-of relative movement between members 28' and 29' is limited'by opposing stop members-3|'- and =32.- whichare-afiixed to members 28"and-29' respectively; When these members abut,-there canbe no further relative withdrawal of member 29' with respect to member28". Thus,

the spacing'between stop members 3!" and32 will determine theamount of parallel relative movement between members 28'- and 29 andhence the amount of rotation of thetipsegment;

Since it isusually desirable to limittthe bending of the tip segment to approximately- 30, thisspacing between the stop members should be very small.- The location of these-stop members, like theirshape, is only by way of illustration.- As illustrated in Fig. 7 their spacing is greatly exaggerated.

Whenthe stop members 3| and-32" abut, since further: relative movement in thesame= direction is impossible, the middle segment then will Y act as-sa single piece similar to thetipsegment as member-36 is further withdrawnt Thus; withdrawalv of member 36- causes withdrawal of pin connection 42 and,- due to the rigidity-o1" mem ber 31, produces rotation of. the-whole.middlesegment about pin4ll'. The middlesegmentwill bend until .the withdrawal of member iit is stopped It. may .be .seen that "when a tubularHmemberis usedtosurround a rod-likemember as in Figs.

3 ande, the parallelism .of the two-members is enforced. Likewise parallelism maybe enforced ber.

ferredaas it. adds. strength .to the..digital-unit andprotects themovement of theinneremember from. interference with'material used to coverthe'. finger mechanism. Nevertheless, any digital unit.

which maygrow out. of thesimpleconfiguratiori illustrated in Big... .7. .withinthe. scope .of. my.-.

invention.

Ifv a:rotational movement about. the; near-hand 1 end of members'flfi' and 3l'-- is superimposed-on the linear-relative movement-of members 36'-and 37'; the bending of the near-hand knuckle in 'a" -real hand will be simulated.-- This rotational:

movement is easily and effectively imposed upon the fingers in the Figs; 3 and 4 preferred version. of my: artificial finger by cylindrical knuckle member 43. In this version of'the artificial finger, tubular outer member 3'! passes through .05;-

lindrical knuckle member 43 at right angles thereto. Thus rotation'of knuckle-'43 simultaneously causes an effective rotation of the whole. finger, including the inner:near-handsegment-rmemben'with other bending operations previously;

described as is illustrated in Figs. 5 and '6.'='

Since the rotation of the knuckle member:43

produces a bending of the whole finger relative to the 'palmof'the'hand, it is necessary to make a connection to'member about which'membern: 3S may rotate r and through which the'force causing-its withdrawal may be supplied." ThiSszT member may be" a shaft 45 parallel to the? knuckle 43. In the-preferred coaxial construc-.---

ition of Figs-3 and 4, the rotation-of'the knuckle" 43 and withdrawal of the inner member 36 is caused bythis means. Rotational movement is advantageously supplied to the knuckle'by a gear connection to the'drive'. 'Theshaft connection-w to end flange 44 of member 35 is-placed in acamslot. If there is rigid connectionabetween the knuckle and the member in which-thecam slot H is formed, as the knuckle'is rotated, theshaft; hencemember 35." will bewithdrawn 'as "the knuckle is rotated.

If the finger should-not be of-coaxial construc--- tion, even simpler means of withdrawal are possible. For instance, the knuckle-and the shaft may be fixed to the hand-in such a way that thenear-hand segment member joined to the knuckleis effectively rotated away from the shaft. As the member joined to the knuckle moves-away" from the'shaft, the-member connected-to the,- shaft moves closerto the knuckle. The connection to the middle segment member on that nearhand-member whichis connected-to the hand-by the shaftnecessarily also moves closer -to the-- knuckle. Thus, efiective withdrawal of this near-hand and middle segment connectionwaswell as the subsequent members is accomplished,

causingthe finger to bend in the same way that it does when moved byother -means. Such a: systemofwithdrawal of one member relative to-- the other "at the .near-handknuckle is illustrated. in-Figs. 8-and9 wherein it is employed with a thumbof myinvention. The system will be ex plained in detail in connectionwith the discus sion of the structureand operation of the thumb. of Figs..8 and .9. Forthe simple grasping movements most commonly required in every day =living, simultaneous movement of all the fingers is. sufiieient.- This.:maybe accomplished by using a singlercylindrical member for the near-hand.. knuckle member 43 through which 'amember-of thenear-handsegmentof each of the-four fingers passes, advantageously at rightanglesthereto- Similarly, bycoupling oneuend of. each of the. members correspondingsto 3B (the-end.being des-.. ignated .44). to the samemember, simultaneous-H withdrawal of. all thesemembersmaylbe accomplished. AshaftmemberAS havingportions per-ependicularto each of theextensionparts.desig -r nated-.44. whereit penetrates each-of said. exten-.-L sions may .be vusecLto. .accomp1ish..this. end.

i seen in Fig.1, the shaft may: be madewithbendsg.

in it in order to avoid collision between it and other parts.

The thumb unit as pictured in Fig. 8 and Fig. 9 is in many respects similar to the fingers previously described. A finger within the scope of my invention might be made using the general type of construction shown for this type of thumb. As pictured, the thumb is composed of a tip segment 50, a middle segment consisting of a tubular member surrounding a rod-like member 52 and a near-hand segment consisting of member 53 of an essentially tubular shape and rod-like member 54. A boss 55 on the tip segment adjacent member 5| furnishes an appendage which fits within member 5! and enables pin 55 to connect members 50 and 5!. A simple pin connection 5'! may be made between tip 55 and middle segment member 52. A boss 58, similar to boss 55, is formed on member 55 and'fits within member 53, thus enabling pin connection 59 between these two members.

The thumb differs from the finger in that it employs an intermediate member between one member of the middle segment and the corresponding member of the near-hand segment, usually the inner member of these segments. In Figs. 8 and 9, rod-like member 5! serves in this capacity and is also rotatably connected, in this case, by pin '59 which joins it to the tubular members of the middle and near-hand segments. Member BI is pin connected to inner middle segment member 52 at its other end by pin 52 which passes through said member BI and through the yoke extension 53 of member 52. A pin 64 at an intermediate point along rod 61 connects inner near-hand segment member 55 to member 6| by means of yoke extension 65 at the end of member .54. The opposite end of member 54 terminates in boss 65 which is penetrated by shaft 6! and thereby pinconnected to the palm of the hand. Member 53 is given rotational movement at its near-hand end where it is connected by boss 68 to knuckle member 59. The knuckle member maybe supplied power through gear 10.

Thumb movement occurs as the rotation of knuckle 59 causes near-hand tubular member 53 to rotate. This rotational movement also causes rod-like member 54 to rotate about shaft 61. Although rotation occurs about both knuckle 59 and shaft 61, the relative position of shaft El and knuckle 59 remains the same. On the other hand, as near-hand segment member 53 rotates, its pin connection '59 becomes further removed from shaft 6! and, by the same token, pin connection 64 to the inner near-hand segment member 54 more closely approaches knuckle member 69. This change in relative position amounts effectively to the withdrawal of pivot 64 relative I to the outer near-hand and middle segment members. This means, here used for producing bending of the thumb, will be recognized as the same means that was generally described as an alternative way to produce bending in the finger.

The effective pull on pin 65 causes member 5| to rotate about pin 59 and to produce a pull through pin 62 upon middle segment member 52.

The resultant pull on pin 51 tends to produce a withdrawal of tip segment 59, but therigid outer member of the middle and near-hand segments 5! and 53 through their connections 55 and 59 oppose such withdrawal. As a result, rotation ofthe tip segment 55 occurs about pin 56. Tip segment 56 will continue to rotate about pin '56 until the movement of rod 52 is stopped by stop .member H. In this instance, the sto member H, which limits the relative movement between the middle segment members, is merely a shoulder on the tubular member 5! against which either member 52 or member 6| will come to rest. Thereafter, the whole middle segment and the bent tip segment 50 will rotate as a whole about pin 59 under the pull exerted upon pin t l.

Figs. 10 and 11 show a modified thumb structure which corresponds to the preferred construction of the finger. Here again, a tip member 55' is pivotally connected through parallel pins 56 and 51 to independent middle segment members 5 l and 52. Member 5i is tubular and coaxially surrounds member '52. The near-hand segment is composed of coaxial tubular member 53' surrounding member 54'. Flanges l2 and 13 on tip segment 55' are used to connect the tip segment to its adjacent segment. The middle segment has a collar 15 surrounding member 5| supporting a yoke flange '14 extending toward and lying on two sides of flange i3 through which is made the in connection 55'. Stop means in the middle segment is formed by opposed radial shoulders 16 and I I formed on members 52 and 5| respectively. A collar 1? surrounds the end of member 5| adjacent the near-hand segment and supports flange 18. Cooperating forked flange member it is aifixed to near-hand segment member 53 at right angles thereto through collar 85. A connection member between the adjacent ends of the inner middle and nearhand segment members 52 and 54' is furnished by member 6|. Member BI is connected at one end to member '52 by pin 62. The opposite end of member 6! is advantageously terminated in a yoke through which passes pin 8! which rides in cam slot 82 formed in plate 83, an extension of member 54'. Cam slot 82 curves away from the middle segment as it approaches the end of the near-hand segment. A knuckle 85, afifixed to the near-hand end of near-hand member 53', is an enlarged portion of shaft member 69'.

This Figs. 10 and 11 type of thumb operation is basically like that of the Figs. 8 and 9 thumb, but in some ways it resembles more closely the finger movements of the construction of Figs. 3-6. Shaft 55 imparts rotational movement through knuckle member 85 to the tubular outer near-hand member 54. Since it is coaxially contained by' member 53', rod-like member 54' rotates with member 53 and in so doing is withdrawn by pin 86, a connection through its nearhand end, which pin rides in cam slot 87. Slot 8? is formed in member 88 which is afiixed to hand palm member 49 through flange 89. The withdrawal of member 54 causes the withdrawal of its extension flange 83 in which is formed the cam slot 82. As member 54 is withdrawn, it causes the withdrawal of member 51' at right angles to the direction of withdrawal of member 5 5 because of the pull exerted on pin 8| which rides in cam slot 82 and because collar (or tubular extension) 88 restricts the motion of member 6| to the direction of its elongation. Withdrawal of member 5| causesthe withdrawal of middle segment member 52 because of pin connection 62. Withdrawal of member 52' tends to cause withdrawal of tip segment 55'. Withdrawal of the tip 50' is impossible because of rigid opposition by the outer members of the middle and near-hand segments. However, the force acting through pivot 51 ultimately produces bending of tip 50 about pin 56'. Bending of tip 55 and withdrawal of middle segment member 52' continues until shoulder 16 of middle segment memnear-hand segment) 11.1061? 52. ands-shoulder 7 l :T'OfEEtIIbQIQIZEmQmbEK =51 --a,b ut. 3 Thereafter. zrotation Qfi thezzwliole. zmiddle segment asa unit 1will.take;pl ace. aroundcpin- 58' due tQ-the continued Withdrawal ofnmember: 6 I :which will cease when pin 8 i. can; move nofurther in .eam slot 82 -(or until, pin SBLCQ-DLmOVEHOQfIlY- ther in cam slot 31), ltmaybeznotedthatpin 8 --and1pin 86. mayalso, be, called shafts in the :same A sensethat shaft 45 isLcalled.shaft ..(seeFig 2).

1 t should be noted that:particularlyl inzthe ..thumb, the near-handse ment need notbe aperpendicular to the:knuckle.- Itis made so inglligs. I 1.0 and ll, but it-maygjust as readily bemade at .anothenangle as in-..thel?.igs. 8:. and 9-construction'. Itis .also true of;the middle. and .near:handsegments that. they may berplaced: 4132 any: angle adesiredright angles. beingzusuallwthe:most con- 2 .venient relative. positioning.

.. It. should-alsmbanoted that members 6 l..,and

; *6]. together ;with their-connections to othenmem- 5 has serve as connection means: betweenhcorre- .spondingnear-hand; andmiddleseement :memubersin Figs.,8 and9iand Figs.'.lQ;and.11 :respec- .tively. hThismember, aszmay beiseen from. these two; examples, may differ. in iform, but. it alwayshas. .the effect of. changing. .the direction. oiimo- ..tion from. one segment to the other.

. .The drive mechanism,v the meanscausingthe bending of. the .fingersand :thumb; maybe. seen in Eigs- 1, and. 2. .Itis picturedfrom. above'injliig.

2.. and is, partiallyzillustratedin. greater. .detail in the. side, partially: sectioned .view .of. Fig...12. As previously.mentioned,.each of the fingerscould be individually actuated,.but, forithepurposes of .most users, itis .sufiicientto have simultaneous bending of the .fingers .andthumb. In .myhand,

Lprefer to use a.gear;connection between the thumb, andfingers knuckles. as a means. ofr-cou- .p these memberstogether so.,that .they may be .drivenby. .thesame power supplynmeans act-- ing; eitheron. theethumb or the fingers knuckle. Thus, .only.-..one-. powerlsupplyl.outputgmeansis necessary to drive my hand.

The meshing of. bevel .gearsj l'lia-ndv lilmakes ,possible the rotation of. the thumb atzsomeangle,

preferably right angles, to .theaxis of rotation. of

,the; fingers along knuckle; 33. This..rtation of thumb and fin erknuckles atright angles simulates the movement of a. normal..human-.-hand.

Prior artificial hands have.-.disr.eg rded...the.iaot vthat bending of, the thumb -.occurs-..about a neara d u laatailar eiangle with the:.fing.er

knuckles. The thumb swingst-hrough alarge. arc which is provided-for byichoosing .a'.. proper..gear

ratio between finger, andthumbknuckles such.

that .the thumbcloses twoor. three timeslfaster than the fingers. Closing of the ,hand.is.;com

.pleted for grasping most ,small. objects-.1133; ..-the

meeting of the, tips Qi-the,thIImbp-andthesiiISt and/ or second fingers. The. thumbtlpi v50. would not meet the fingertips. in .a..natural..manner were the axes of, bending at theioints between the tip and middle segment 1 and between .the middle and nearrhandsegmentsparallel to the axis of rotation provided by shaft 69. 'I' o.;pr.eventthe thumb from closing directly. across the,palm of the hand, it is well to provide itheijoints. between-the tip and middle e mentsand'ioints between the middle and nearrhand segments; with axes of bending whose perpendiculan.planesiare always perpendicular to the planes perpendicular toshaft 69 (the jointbetweenthe: palmiand, the It is not essential that .these perpendicularaplanes be actually; perpen- ,,dic,ular, but theyshould preferably be at .angles of: betweenf fi? and-190. -11 .is also interesting to note that should the near-hand segment-.ofithe ythumh-be rotated 9Qnwith respect tontsnpezr position: shown; the.rconnectionsacbetweenz the tip and middle. se ments-and. the middleiandmear- A hand e ments ofvtherthumb :shouldc hembswessentiallyparallel toi the correspondingconnec- -tlOI1S.'lI1:l'/h6 fingers; In such-position, therbendingof the thumb andfingerswill beimmmosite directions; hence --toward eaclriothenfrwhich accounts forv the superior :graspingrability :crfnmy hand. Even {relatively large objects, inzthemrder of size of a baseball; or largenmambezemeped by i 7 my: :hand, whereas they-, could: 10122 be; naturally swing'of; the thumb. permitafnhe (closing: ofithe hand upon :suchrelativelyglargez objects .incpicking them; up qwhereaapriorartzhandswiould have i to rely, primarily aupon" wedging: effects.

grasped, if at; all, by=prlor1art:hands.;1:.'1he wide Asipreviously described, the near-handse -ment member 36 is withdrawmwwhilegmemberizfluis a rotated in order to producer-"Inger; bendinauf All {our fingers are; rotated, about r.knuckle,- l3:z a the members corresponding to flare-simultaneously withdrawn, by the withdrawal: ofirshaitrfi ,--whichejoins. them. 1Shaft-45:may. ihave. bendstin it, as previously mentioned, asrlong asthosemortions penetratin end, portions: 44 ofimembeniii ,aregparallel, to knuckle fl; Rotationali movement may beimparted -to.-;knucklei=43'rbyc:giear member 43 held in placey-a ainst knuckleikiiby screws 93 or other rnea ns,.= whichigeamhaszithe I same center, i of rotation; asr.-.'knucklea.l3.. ezGear --member 94; has teeth-which onn seand-mesmwith those of-gear 4B.- A camnslotrSi-is cutdmrgeatrfll and thr ugh this. mrDfiSSQSz-Shfift: games-m slot mightotherwise be cut imanyanembcnrigidly connected to palm- 49.-;;The.-pin- 96::connects gear e l-and-fiangemember Blawhich isadvantageous- 1y: fix t thepow nunihhQusing-.99i;wlrich;is.

in turn, rigidly .afii-xed to .-palm;.49. :-R,otational :movement oigear fl4gaboutipin 96.:is;.cansed:by the advance of member; 98-r-which-isreoupletlito the power supply. outputzmeans'..f The rotation of gear- $4 in turn-causes-rotation:ofixearil :hence knuckle .43. .Movement Offthfi camislct fl as well-as the-movement of-member 3.6.nhanges the; position of: shaft 45 in the canxslot This change in position producesa withdrawal otshaft 45-.and; all members attached thereto. :The. drive ,unit is rigidly aflixed to the-hand alrmzportion 'otally, connected to knuckle and: shaft-elements. .This rigid connection to-the- .Dalm, wand: hence .toeachother, provides axi-pathufrom:shafts-to knuckle through :which theppposing-aforces causing finger movement may betransm-itted.

The amount of fingenbend-ing is limitedzby-the ,length of the cam;slot 95.,;i When -.rod-a45;strikes the: end ofthe slot, ,further. withdrawalofzmember- 33 is .notpossible. A; spring'.-meansvi;00:aor

order to run on energy supply by batteries. Motor I02 drives cam I03 which in turn produces reciprocation of driven piston member I04 which moves back and forth under the loading of spring I05. Each stroke which decreases the size of chamber I03 and thereby compresses the fiuid therein forces open ball type check valve III! which lies between chamber I06 and chamber I08. When the pressure in chambers I06 and I68 is equalized, check valve I31 will close under the pressure of its spring I09. As the cam I03 permits, the volume of chamber I06 is again increased by forcing piston I04 back under pressure applied by spring I05. Because of the reduced pressure within cylinder I66, more fluid is permitted to enter chamber I06 through ball type check valve III, normally held shut against shoulder II3 by the fluid and the pressure of spring II2. Again as cam I03 causes piston I04 to compress the fluid in chamber I36, the valve I! opens and permits fluid to enter chamber I08, thereby causing the driving piston H4 to be driven forward, thus advancing output shaft 98. The advancing output shaft initiates hand movement as previously described. Vents II permit piston II4 to move freely without back pressure due to the compression of air behind piston I I4. A resilient toroidal ring II 6, commonly called an O-ring, may be used as sealing means between the piston II4 and the walls of chamber I68.

When it is desired to open the hand, solenoid II8 may be excited in order to exert pressure on piston H9 which thereby opens check valve I20, which may be of the type used in pneumatic tires, thereby releasing the pressure in chamber I 66. Spring I60, or any other spring means positioned for the purpose, then causes the return of the hand to open position.

Referring to Figs. and 16, the support and socket apparatus for use with the artificial hand by the wrist or fore-arm level amputee are shown in elevation and in partial section respectively. The socket I25 is advantageously held in place by a flexible tubular support member I26 which fits around the upper arm and is held in place by means such as straps I27. The tubular support member I26 is advantageously connected to the socket I25 by means of strap members I28 on both sides of the arm adjacent the elbow joint. In order to insure a maximum of freedom, each strap member I23 is connected at one end to socket I25 by means of a pin I29 and at its other end to support member I23 by means of pin I33. In order to hold the socket I25 in place, the straps I28 should be able to expand or contract their lengths between pins I29 and I30. Hence they are advantageously made of rubber or similar material. The rubber may be reinforced by a metallic strip which has longitudinal slots I3I and I32 in which the pins move as the distance between them increases or decreases. The reinforcing metal is of great advantage to keep the socket in place where heavy pulls on the socket are expected.

Fig. 16, like Fig. 2, shows in cross section the wrist portion of the artificial hand which is also shown in a different and larger elevational view in Fig. 17. The Wrist consists of a rotatable member I33, to which the artificial hand is affixed, and a stationary member I34, amxed to the socket I 25. Member I33 is easily rotatable relative to member I33 because of ball bearings I35. Rotatable member I33 advantageously lies within stationary member I34. Ball bearings I35 advantageously run in a circumferential groove 14 I36 around the rotatable member I33. These balls may be retained in placeat the bottom of radial holes in stationary member I34 by means of screws I31. A hole I38 may be left in member I 33 for solenoid II8.

The cables I 39a and I391) each haveone end aifixed to the rotatable member I33 at some oficenter position. It is usually convenient for the same off-center point to be used for both cables so that a single screw I4I, or similar means, is sufficient to afiix the ends in place. The otherwise unconnected end of one of the cables is attached to the upper arm above the elbow, close to the elbow. The otherwise unconnected end of the other cable is also attached to the upper arm close to the elbow but around the arm from the first cable. With a forearm amputation the arrangement illustrated in Figs. 15 and 16 makes it possible to afiix that end of each cable adjacent the elbow to support member I26. Attachment to other members in this same region is also possible, of course. The cables I334) and I331) are advantageously surrounded byvtubular members I40a and I401) which serve the dual purpose of shield and guide for the cables. The guiding function may be accomplished merely by afiixing simple. guide members such as loops, in the same location in which the ends of the tubular members I401) and I-40b would otherwise be fixed. A pair of guides should be fixed near the periphery of the stationary wrist member I34 or adjacent thereto on the support or socket I25. These guides should be widely spaced apart. Similarly spaced guides should be placed at the other end of the forearm adjacent the elbow. These guides may be ailixed to socket member I25 in the case of a forearm amputation. H

Rotation of the wrist occurs by means of the pull on the cables I39a and I391) which pass the socket I25 through tubular members I 401). and I431) respectively on the way to the support member I26. The points on the socket at which the ends of tubular members Mile and I431) are affixed, the points at which the ends of cables I35a and I361?) are affixed, and the movement of the wearer determine the amount of wrist movement produced. The end of the tubes I40a and I461) are fixed at widely spaced points around the socket I25 and the points of attachment of cables to the support I25 are also widely spaced. As the arm is bent at the elbow the distance between the point of affixing the end of each cable and the end of its tubular guide I46a or I401) will vary. In bending, this distance decreases for cable I39a and increases for cable I39b. In straightening, this distance increases for cables I391). and decreases for cable I362). For smooth functioning of the wrist mechanism the sum of these distances for cable I331; and cable I331) should always be constant. This take upand release eifect on the cables may be seen for two positions by reference to Figs. 15 and 16. It causes a pull on screw I4I resulting in rotation of rotatable member I33 which, of course, turns the whole hand. When the arm is bent, cable I391) Will be under tension and cause a pull on screw I4I thus producing rotation in one direction. The further apart the near-wrist ends of tubular members I40a and I 401), the larger the angl through which the wrist may turn.

The further off-center the screw MI is placed, the larger the lever arm presented to the pull of the cables I331: and I391), hence the easier it is to turn the wrist. However, the closer to the center the screw is located the less the move? "515 :m'ent of cables necessary to turn the wrist through: any given" angle. *Unpredictable *wrist "movement is prevented by keeping thescrew- 'I II withinthe--smallerangle formed by the -intersection at the axis of-rotation of extensions of lines through said axis andthrough the ends of "tubes-140a and Mill) respectively.

- The turning of the wrist produced by bending th -elbow is particularly valuable when-convey- -ingobjects to the'mouth. This Wrist-movement 1o "is-the one most frequently used and is-hencemost important to amputees.

Fig. l8-shows in cross section a switch-used to actuate my artificial hand. The same switch is shownin-elevationin Fig. 16 as mounted on "or similar material, is sandwiched*conductive eo -*strip I46, which is-preferably made of spring material and held in place by rivets i 41 or-sim- 'ilar -means. The conductive *strip 146 *may* be directly connected to a circuit-lead M8- or may "be connected asshown through a rivet-"Ml or a whole may be held in place by strap means I 53 '35 "which encircle socket I25 and permit adjustment of the pressure with which the switches are held in place. Thistype of switch is closedby pressure produced whenmuscles are flexed. Two such-40 "switches are used with-my artificialhand; one to close the-hand and the other to open it. Of course, the switch shown in Fig. l8-may-bemodified in order to take advantage of particular circumstances while retaining the basic'idea of flexible metallic members which are closed against contact-means by the flexing of-amuscle.

- In the case of wrist level amputationsby care- "fully selecting the location of the switches,

natural muscle movements used in opening and 5 closing the hand may be employed to-close the respective switches and thusopen and 'close' the hand in a natural way. Thus, it is relatively easy to learn to use my artificial hand;:although -learing is still required in order'to control the =amount of pressure applied by the fingersp'It is obvious, however, that even musclesnotnormally used in-movingthe-hand may berused to produce movement of myartificial hand.

- A circuit of the sort illustrated schematically so inF-ig. 19 may be used to operate the artificial hand and produce movement therein. Energy may be supplied across terminals I 55-by a battery which may be carried in any convenientmanner anywhere on the body of the wearer. Since only a pair of leads is required to reach the battery, it 'seems unwise to add weight byincluding the "battery in the arm. Onelead fromthe-battery is joined to leads 48 and H38, which lead through their respective switches I60 and IBI and thence through leads I52 and' IE2 to-one side of the motor I02, or its equivalent; and one side of. the solenoid I I8, or its equivalent, respectively; The lead on the other side ofthe battery connects to Metallic contact -point 30 ""tively.

' "-Variouselements of'my'artificial hand'mayalso :-'be"used to advantagealone orin combination rwith other parts" of my-hand inother types of :"a'rtificial'hands. "For instance; the digital'units should"be'valuable-with many types of hands "now in common use; The fluid pressure-power supply might-be used to move other types of "artificial'hands. The-wrist structure, in this con- "'n'ectionpmay" be applied to almostany artificial hand.

*It-mayalso be-noted-that the constructions of "the digits suggested herein may be modified and used-alone or with other-parts of-my invention to produce agrappling,scratching or similar means not necessarily classifiable amen-"artificialhand; Anysu'ch variations of m'y invention as described herein,- used in simple or combined form; are within the scope of I my invention.

I claim:

1-."An artificial digit comprising a tip segment, a middle segment consistingof two independent members, one of which is elongated;'-aneansdimit- "ing the relative motion ofthe middle-segment -members-in thedirectionof elongation when "bending the digit-,- means rotatably connecting each of the middlesegment membersto the tip segment sothat the resultant axes of rotation are parallel, a near hand segment consisting of 'twoindependentmembers, one of which is elongated and means 'rotata-bly connecting eachof the near-hand segment members to the corre- 'spondingmember in the=middle segment so that the resultant axes or rotation are parallel.

2-. An artificial digit comprising a tip segment, *a plurality of middle segments each consisting of two independent members; one of which is elongated-means limiting the relativemotion of each of the middle segment members in e'a ch middle segment: in the direction' of elongation -when bending the digit; -means I rotatabl-y "connecting the adjacent ends'of corresponding'members and ends of the middle segment-membersadjacent the tip segment to that segment so-' that there- "sultant axes of rotation are paralleL'a-near-hand segment consisting of two I independent members, one ofiwhich elongated, and means i'otat'ably connecting each of the near-handsegment members tothe correspondingmember in-the middle segment so that the resultant 'axesof ---rotatio'n are parallel.

3.:An artificial-digit comprising a tip segment, a middlesegment consisting of two independent, "elongated members, stop means'limiting the relative motion of the rniddlesegment members in thedirection ofelongation when bendingthe digit, means rotatably connecting that end=of each: middle segment member adjacent the tip segmentto said tip segment so that the resultant axes of rotation are parallel, a near-hand seg- 'ment I consisting of 1 two I independent, elongated members, and Y means -rotatably connecting one end of each near-hand segment member tothe adiacentotherwise unattached end of the corresponding member in the middle segment sothat the resultant axes of rotation are parallel.

4. An artificial digit comprising a tip segment, a middle segment consisting of two independent, elongated, essentially parallel members, stop means on themiddle segment members limiting theirrelative motion in the direction of elongation when bending. thetdigit', means rotatably connecting theend of each middle segment memtheother side of the motor I02 and theother side"7'5 'benadjacent'the tip segment'to the tip segment so that the resultant axes of rotation are parallel, a near-hand segment consisting of two independent, elongated, essentially parallel members, and means rotatably connecting one end of each near-hand segment member to the adjacent, otherwise unattached end of the corresponding member of the middle segment so that the resultant axes of rotation are parallel.

5. An artificial digit comprising a tip segment, a middle segment consisting of two independent elongated members, stop means on the middle segment members limiting the relative motion in the direction of elongation when bending the digit, means close to one another relative to the length of the middle segment rctatably connecting one end of each middle segment member to the tip segment so that the resultant axes of retation are parallel, a near-hand segment consisting of two independent, elongated members, and means close to one another relative to the length of the near-hand segment rotatably connecting one end of each near-hand segment member to the adjacent, otherwise unattached end of the corresponding member in the middle segment so that the resultant axes of rotation are parallel.

6. An artificial digit comprising a tip segment, a middle segment consisting of two independent, elongated, essentially parallel members having abutting shoulders acting as stop mean limiting their relative motion in the direction of elongation when bending the digit, means attached to one middle segment member surrounding the other member and tending to keep said middle segment members essentially parallel, means rotatably connecting one end of each middle segment member to the tip segment so that the resultant axes of rotation are parallel, a nearhand segment consisting of two independent, elongated, essentially parallel members, and means rotatably connecting one end of each near-hand segment member to the adjacent, otherwise unattached end of the corresponding member in the middle segment. so that the resultant axes of rotation are parallel.

7. An artificial digit comprising a, tip segment, a middle segment consisting of two independent members, one of which is essentially tubular in shape and surrounds the other, stop means formed on the middle segment members which limit the relative motion between the middle segment members in essentially the direction of elongation of the inner member when bending the digit, means rotatably connecting one end of each middle segment member'to the tip segment so that the resultant axes of rotation are parallel, a near-hand segment consisting of two independent members, one of which is essentially tubular and surrounds the other, and means rotatably connecting one end of each near-hand segment member to the adjacent, otherwise unattached end of the corresponding member in the middle segment so that the resultant axes of rotation are parallel. I

8. An artificial digit comprising a tip segment, a middle segment consisting of a pair of coaxial members having stop means limiting relative axial motion when bending the digit, means ro-' tatably connecting one end of each middle segment mem'ber to the tip segment'so that the 'resultant axes of rotation are parallel, a near-- hand segmentconsistingof two independent co-I axial members, and means rotatably connecting one end of each near-hand segment member to the adjacent, otherwise unattached end of the corresponding member in the middle segment so that the resulting axes of rotation are parallel.

9. An artificial digit comprising a tip segment, a middle segment consisting of two independent coaxial members having opposing radial shoulders which act as stop means restricting relative axial movement when bending the digit, means rotatably connecting one end of each middle segment member to the tip segment so that the resultant axes of rotation are parallel, a near-hand segment consisting of two independent coaxial members, and means rotatably connecting one end of each near-hand segment member to the adjacent otherwise unattached end of the corresponding member in the middle segment so that the resultant axes oi rotation are parallel.

10. An artificial digit comprising a tip segment, a middle segment consisting of two independent coaxial members having opposing radial shoulders which act as a stop limiting relative axial movement when bending the digit, means, close to one another relative to the length of the middle segment, rotata'bly connecting one end of each member of the middle segment to the tip segment so that the resultant axes of rotation are parallel, a near-hand segment consisting of two independent coaxial members, and means, close spaced to one another relative to the length of the near-hand segment, rotatably connecting one end of each near-hand segment member to the adjacent, otherwise unattached end of the corresponding member in the middle segment so that the resultant axes of rotation are parallel.

11. An artificial digit comprising a tip segment, a middle segment consisting of two independent coaxial members having opposing radial shoulders which act as a stop limiting relative axial movement when bending the digit, means, close to one another relative to the length of the middle segment, rotatably connecting one end of each member of the middle segment to the tip segment, a near-hand segment consisting of two independent coaxial members and means, close to one another relative to the length of the nearhand segment, rotatably connecting the end of each near-hand segment member to the ad acent, otherwise unattached end of the corresponding member in the middle segment, all of such rotate able connections being made so that all of the resultant axes of rotation are parallel.

12. A thumb for an artificial hand comprising a tip segment, a middle segment consisting of two independent members, one of which is elongated, stop means limitingthe relative motion essentially in the direction of elongation when bending the thumb, means rotatably connecting one end of each middle segment member to the tip segment so that the resultant axes of rotation are parallel, a near-hand segment consisting of two independent members, one of which is elongated, coupling means interposed between the otherwise unattached end of one middle segment member and the adjacent end of the corresponding near-hand segment member whereby the direction of motion is translated, and means rotatably connecting said coupling means to the respective members and rotatably connecting the adjacent ends or" the remaining middle and near-hand segment members so that the resultant axes of rotation are parallel.

13. A thumb for an artificial hand comprising a tip segment, a middle segment consisting of two independent elongated members, stop means limiting relative motion essentially in the direction of elongation when bending the thumb, means r0 ace-ogre? 19 tatably connecting one end of each middle segmentmember to the tip. segment so that the result- Vantaxes of rotation are parallel, a near-hand segment consisting of two'independent members, .coupling means'interpose'd'between the otherwise .unattached end of one middle segment member tation are parallel.

14. A'thumb for an artificial hand comprising a .tip segment, a middle segment consisting of two independent elongated members, one of which essentially surrounds the other, stop means on the middle segment members limiting'the relative motion of the middle segment members in the direction of elongation when bending the thumb,

.means rotatably connecting one end of each middle segment member 'to the tip segment so that'the resultant axes of rotation are parallel, a near -hand segment consisting of two independent members, one of which essentially surrounds the other, coupling means interposedbetween the otherwise unattached end of one midthe segment member and the adjacent end of the corresponding near-hand segment member whereby the direction of motion is translated, and means rotatably connecting said coupling means "to the respective middle and near-hand segment members'and rotatably connecting the adjacent ends'of'the remaining middle and nearhand segment members so that the resultant axes of rotation are parallel.

'15. A thumb 'for an artificial hand comprising a tip segment, a middle segment consisting of a rod-like 'inember and a surrounding tubular member, stop uneans on the middle segment members limiting the relative motion of the middle segment members essentially in the direction of elongation when bending the thumb, means rotatably connecting one end of each middle segment member to the tip segment so that the resultant axes of rotation are parallel, a near-hand segment consisting of a rod-like member and a surrounding tubular member, a rod-like coupling means interposed between the otherwise unattached end or the rod-like middle segment member and the adjacent end of the rod-like near-hand se ment member whereby the direction of motion is translated, and means rotatably connecting said coupling means to the rsepective middle and near-hand segment members and connecting the adjacent ends of the tubular middle and near-hand segment memhere so that the resultant axe of rotation are parallel.

'16. A thumb for'an artificial hand-comprising a-tipsegment, a middle segment consisting of a rod-like member and a surrounding tubular member, stop means consisting of a shoulder on the tubular member limiting the relative movement of the'rod-like member in the direction of elongation when bending the thumb, means rotatably connecting one end of each middle segment member to the tip segment so that the resultant axes of rotation are parallel, a nearhand segment consisting of a rod-like member and 'a surrounding tubular member, a rod-like coupling means interposed between the otherwise unattached end of the rod-like member of the middle segment and the adjacent 'end of the :rod-like near-hand segment member and means rotatably connecting one end of said coupling means to some portion of the tubular members and other points on the coupling means to the respective rod-likemembers and connecting the adjacent ends of the tubular middle-and near-hand segment members so that the resultant axes of rotation are'parallel.

'17. A thumb for an artificial hand comprising a tip segment, a middle segment consisting of independent coaxial 'members which have opposed shoulders limiting relative motion of the middle segment members in the direction of elongation when bending the thumb, means rotatably connecting one end of each middle segment member to the tip segment so that the resultant axes of rotation are parallel, a nearhand segment consisting of independent coaxial members, the end'of the inner member of the near-hand segment adjacent the middle segment having therein a cam slot which curves away from the middle segment as it approaches the end of said near-hand segment member, a tubular extension at an angle with the outer near-hand segment member attached to said outer member in a fixed position relative thereto, a coupling means placed coaxially within the tubular extension and interposed between the otherwise unattached end of the inner member of the middle segment and the cam slot end of the inner member of the near-hand segment, and means rotatably connecting said coupling-means to the respective inner members of the middle and-near-hand segments, including means which lies within the cam slot, and rotatablyconnecting the outer member of the middle segment to the tubular extension of the outer member of the near-handsegment sothat the resultant axes of rotationare parallel.

18. Means causing the bending of artificial digits by applying parallel opposing :forces to the memberszof the near-hand segment thereofcomprising knuckle means aflixed to the -nearhand end of one of the near-handsegment members and supplied rotational movement by a drive meanslshaft means parallel to the knuckle means to whichshaftisiaflixedthenearehand end oft'ne other near-hand segment member and about which shaft said member is free to rotate and rigid support means between the knuckle and the shaft.

19. Means causing :the bending of artificial digits by lapply'ing parallel opposing forces .to the members of the near-hand :segment thereof comprising knuckle means amxed to the nearhandend of theouter membei of the near-hand segment and supplied rotational movement :by a drive means, shaft means parallel-t0 the knuckle means to which shaft is afii-xed the near-hand end of the inner member'of the near-hand segment member and-about which shaft said member is free to rotate.

20. Means causing the bending of artificial digitsby applyingparallel opposing forces to-the members-of the-near-hand segment thereof comprising knuckle means afiixed to the near-hand end 'of 'the outer member 'of the near-hand segment and "supplied rotational movement by a drive means and shaft =means parallel to the knuckle means aifixed to 'the'near-hand end-of the inner member of the near-hand segment about which-shaft said member is free to rotate and which shaft is 'fixedrelative to "the knuckle means so that as the outer 'member is rotated 21 away from said shaft, the shaft will cause a pull on the inner member.

21. Means causing the bending of artificial digits by applying parallel opposing forces to the members of the near-=hand segment thereof comprising knuckle means affixed to the near-hand end of the outer member of the near-hand segment and supplied rotational movement by a drive means, means limiting the direction of all relative movement between the near-hand segment members to that in the direction of elongation, shaft means parallel to said knuckle means afiixed to the near-hand end of the inner member of the near-hand segment about which shaft said member is free to rotate and which shaft is free to move along a directed path and rigid support means between the knuckle and the shaft in which support means a cam slot is formed to direct the movement of the shaft.

22. Means causing the bending of artificial digits by applying parallel opposing forces to the members of the near-hand segment thereof comprising cylindrical knuckle means to which is aifixed the near-hand end of the tubular member of the near-hand segment and which is supplied rotational movement by a drive means, an inner member of the near-hand segment having a diameter such that it will pass through the knuckle means and through the end of the tubular near-hand member in sliding contact therewith which inner member extends beyond the knuckle means on the side opposite from the digit, shaft means parallel to the knuckle means afiixed to the near-hand end of the other nearhand segment member about which shaft said member is free to rotate and rigid support means between the knuckle and the shaft.

23. Means causing the simultaneous bending of a plurality of artificial fingers by applying parallel opposing forces to the members of the near-hand segment of each finger comprising knuckle means affixed to the near-hand end of one of the near-hand segment members of each finger and supplied rotational movement by a drive means, shaft means parallel to said knuckle means afiixed to the near-hand end of the other near-hand segment member of each finger about which shaft means said member is free to rotate and rigid support means between the knuckle and the shaft means.

24. Means causing the simultaneous bending of a plurality of artificial fingers by applying parallel opposing forces to the members of the near-hand segment of each finger comprising cylindrical knuckle means to which is affixed the near-hand end of the tubular member of the near-hand segment of each finger and which is supplied rotational movement by a drive means, inner members of the near-hand segment of each finger which pass through the knuckle means and through the end of the tubular near-hand member in sliding contact therewith and extend beyond the knuckle means on the side opposite from the digit, a shaft member having a portion which lies in a cam slot and having portions which penetrate the near-hand end of the inner members of the near-hand segment of the fingers which portions are parallel to the knuckle means and form a rotatable connection, and rigid support means between the knuckle and the shaft member in which support means a cam slot is formed to direct the movement of the shaft member.

25. Means causing the simultaneous bending of a plurality of artificial fingers by applying parallel opposing forces to the members of the nearhand segment of each finger comprising cylindrical knuckle means to which is afiixed the near-hand end of the tubular member of the near-hand segment of each finger, coupling means joining a drive means and the knuckle means including a pair of intermeshing gears, the gear afiixed to the knuckle means having an axis of rotation which coincides with that of the knuckle means, inner members of the near-hand segment of each finger which pass through the knuckle means and through the end of the tubular near-hand segment member in sliding contact therewith and extend beyond the knuckle means on the side opposite from the fingers, a shaft member having a portion which lies in a cam slot and having portions which penetrate the near-hand end of the inner members of the near-hand segment of the finger which portions are parallel to the knuckle means and which portions form a rotatable connection means, and support means between the knuckle means and the shaft member including the gear meshing with the gear on the knuckle means in which first mentioned gear is formed a cam slot to'direct the movement of the'shaft member.

26. Means causing the simultaneous bending of a plurality of artificial fingers and an artificial thumb by applying parallel opposing forces to the members of the near-hand segment of each digit, comprising knuckle means affixed to the near-hand end of one of the near-hand segment members of each finger perpendicular thereto, knuckle means affixed to the near-hand end of one of the near-hand segment members of the thumb, said thumb knuckle being approximately at right angles with the finger knuckle means, means coupling together the thumb and finger knuckle means and enabling said knuckle means to rotate at different speeds, drive and coupling means supplying rotational movement to one of said knuckles, shaft means parallel to the respective knuckle means aifixed to the near-hand end of the remaining near-hand segment member of each finger and of the thumb, about which shaft means said member is free to rotate, and rigid support means between the knuckle and the shaft means.

27. Means causing the simultaneous bending of a plurality of artificial fingers and an artificial thumb by applying parallel opposing forces to the members of the near-hand segment of each digit comprising knuckle means aflixed to the near-hand end of one of the near-hand segment members of each finger perpendicular thereto, knuckle means affixed to the near-hand end of one of the near-hand segment members of the thumb, said thumb knuckle being approximately perpendicular to the finger knuckle, gear coupling between said thumb and finger knuckles such that the rotation of the thumb knuckle occurs at a more rapid rate than the rotation of the finger knuckle, drive and coupling means supplying rotational movement to the finger knuckle, shaft means affixed to the near-hand end of the remaining near-hand segment member of each of the fingers and shaft means affixed to the near-hand end of the remaining near-hand segment member of the thumb, each shaft means being parallel to the respective knuckle means, and rigid means between knuckle and shaft means.

28. Means causing the simultaneous bending of a plurality of artificial fingers and an artificial thumb by applying parallel opposing forces to the members of 1 the -.near hand-rsegmentuof each digit comprising knuckle means aifixedwto .the near-hand end :of the "tubular near-hand :segment member of eachfinger, perpendicularthereto, knuckle means aifixed -.to".the nearehand: end of the tubularnearehand segment membenof-the thumb, said thumb knuck-lezbeingapp oximately perpendicular to the finger knuck1e,: gear coupling between said thumb and finger .--knuckles such that the 'rotationpf .the thumb knuckle occurs at a more rapidratethanithe rotation of the finger knuckle, "coupling means joining :a drive means and the finger knuckle means, said coupling meansv including a-pairof'intermeshing gears, one of said gears being'aflixed to .the knuckle means so that its axisof rotation coincides with that-of theknuckle-means, ar-shaft member having a portionlthat liesiin a cam.-slot and having portions "which penetrate the nearhand end of the :inner membersiof the nearhand segment of each fingerwhichgportionsare parallel to the finger knuckle means zandwform rotatable connection: means, shaft :meanspenetrating the near-hand-endfof the inner -nearhand segment member. ofithe thumb which-shaft means is parallelto the :thumb knuckle means, support means between .the finger. knuckle rand 24 theshaft. member-ewhichz'support meansincludes the cam slot and support -means between :the thumb knuckle and the thumb .shaftmeans.

THEODOREOPUSZE-NSKI.

References Cited in the file of this ,patent UNITED :ESTATES PATENTS Number Name I Date 26,378 Selpho-et a1. Dem-6,1859 984,179 Aydt Feb. 14,1911 999,484 Carnes Aug. 1,1911 1,247,077 Caron Nov. 20, 1917 1,377,956 Anderson May 10, 1921 2,172,167 Leventhal "Sept."5, 1939 2,408,880 Rebers Oct. 8, 1946 2,442,530 Eberle et'al. June 1, 1948 2,457,305 Dale Dec. 28, 1948 2,486,746 Jinkins -Nov. -1, 1949 2,549,716 Simpson Apr. 17, 1951 2,567,066 Goldman Sept. 4, 1951 2,568,051 Catranis Sept.18, 1951 2,580,987 Alderson Jan. 1,1952

FOREIGN PATENTS Number Country ?Date 101,864 Great Britain 'Ju1y26, .191'7 

